Chemical Composition Data of the Main Stages of Copper Production from Sulfide Minerals in Chile: A Review to Assist Circular Economy Studies

[EN] The mining industry has faced significant challenges to maintaining copper production technically, economically, and environmentally viable. Some of the major limitations that must be overcome in the coming years are the copper ore grade decline due to its intense exploitation, the increasing requirements for environmental protection, and the need to expand and construct new tailings dams. Furthermore, the risk of a supply crisis of critical metals, such as antimony and bismuth, has prompted efforts to increase their extraction from secondary resources in copper production. Therefore, improving conventional processes and developing new technologies is crucial to satisfying the world's metal demands, while respecting the policies of environmental organizations. Hence, it is essential that the chemical composition of each copper production stage is known for conducting these studies, which may be challenging due to the huge variability of concentration data concerning the ore extraction region, the process type, and the operational conditions. This paper presents a review of chemical composition data of the main stages of copper production from sulfide minerals, such as (1) copper minerals, (2) flotation tailings, (3) flotation concentrates, (4) slags and (5) flue dust from the smelting/converting stage, (6) copper anodes, (7) anode slimes, (8) contaminated electrolytes from the electrorefining stage, (9) electrolytes cleaned by ion-exchange resins, and (10) elution solutions from the resins. In addition, the main contributions of recent works on copper production are summarized herein. This study is focused on production sites from Chile since it is responsible for almost one-third of the world's copper production.This research was funded by CNPq (Process 160320/2019-4), Cyted (Network 318RT0551), ERAMIN2 (Network Sb-RECMEMTEC, FINEP--Brazil, ANID--Chile, and AEI--Spain) and Direccion de Investigacion Cientifica y TecnolOgica (DICYT) of the Universidad de Santiago de Chile. This study was financed in part by the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior--Brasil (CAPES)--Finance Code 001 (Process 88887.364537/2019-00).Santana-Barros, K.; Vielmo, VS.; Garrido Moreno, B.; Riveros, G.; Cifuentes, G.; Moura Bernardes, A. (2022). Chemical Composition Data of the Main Stages of Copper Production from Sulfide Minerals in Chile: A Review to Assist Circular Economy Studies. Minerals. 12(2). https://doi.org/10.3390/min1202025012

Eficiencia del sector del comercio al por mayor de prendas de vestir y calzado: pertenencia a un grupo y tamaño.

El objetivo de este trabajo es estudiar el grado de eficiencia técnica de las empresas del sector del comercio al por mayor de prendas de vestir y calzado.En primer lugar, se ha analizado el contexto histórico del sector, aportando datos económicos, prestando atención al grupo INDITEX. Tras ello, se han calculado los grados de eficiencia técnica de una muestra de 357 empresas extraída de la base de datos SABI, mediante el método envolvente de datos (DEA). Esto me ha permitido i) estudiar como afecta el hecho de pertenecer o no a un grupo a la eficiencia, y ii) analizar el impacto que puede tener el tamaño de las empresas en la eficiencia. Los resultados han sido satisfactorios ya que ambas variables influencian positivamente al grado de eficiencia técnica de las empresas.<br /

Efecto de la marcha nórdica sobre la condición física en personas mayores sanas: una revisión sistemática y metaanálisis

59 p.Antecedentes: Los cambios asociados al envejecimiento en estructuras y funciones corporales impactan en la condición física, funcionalidad y calidad de vida de las personas mayores (PM). La Marcha Nórdica (MN) es un tipo de entrenamiento que ha demostrado efectos en distintas cualidades motoras que contribuyen a la condición física en distintas poblaciones. Objetivo: Analizar los efectos de la MN sobre parámetros de la condición física en PM sanas a través de una revisión sistemática y metaanálisis. Método: Se realizó una búsqueda de ensayos clínicos controlados y aleatorizados de intervenciones con MN en PM en base de datos, Pubmed, Scopus, Web of Science y Proquest. Las medidas de resultado principales fueron cualidades motoras relacionadas con la condición física tales como: fuerza, flexibilidad y equilibrio. El metaanálisis fue realizado utilizando Review Manager versión 5.2. Conclusiones: La MN mejoró significativamente la fuerza de miembros superiores (MMSS), miembros inferiores (MMII) y flexibilidad de MMII, no así el equilibrio dinámico. Se requieren mayor cantidad de estudios, con mejor calidad metodológica, que permitan confirmar estos hallazgos y recomendar la MN como una intervención efectiva para la mejora de la condición física en PM. / ABSTRACT: Background: Aging-associated changes in body structures and functions impact on physical fitness, functionality and quality of life in the elderly (PM). Nordic walking (NM) is a type of training that has demonstrated effects on different motor qualities that contribute to physical fitness in different populations. Objective: To analyze the effects of NM on physical fitness parameters in healthy MP through a systematic review and meta-analysis. Methods: A search for randomized controlled clinical trials of MN interventions in PM was performed in Pubmed, Scopus, Web of Science and Proquest databases. The main outcome measures were motor qualities related to physical fitness such as: strength, flexibility and balance. Meta-analysis was performed using Review Manager version 5.2. Conclusions: NW significantly improved MMSS strength, MMII and MMII flexibility, dynamic balance did not. More studies, with better methodological quality, are needed to confirm these findings and to recommend NM as an effective intervention for improving physical fitness in PM

¿Basta con escribir?: creación de un archivo virtual de prácticas creativas sobre artistas activistas en el Grado en Estudios Ingleses

Memoria ID-102. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2021-2022

Consensus interpretation of the p.Met34Thr and p.Val37Ile variants in GJB2 by the ClinGen Hearing Loss Expert Panel

Purpose: Pathogenic variants in GJB2 are the most common cause of autosomal recessive sensorineural hearing loss. The classification of c.101T>C/p.Met34Thr and c.109G>A/p.Val37Ile in GJB2 are controversial. Therefore, an expert consensus is required for the interpretation of these two variants. Methods: The ClinGen Hearing Loss Expert Panel collected published data and shared unpublished information from contributing laboratories and clinics regarding the two variants. Functional, computational, allelic, and segregation data were also obtained. Case-control statistical analyses were performed. Results: The panel reviewed the synthesized information, and classified the p.Met34Thr and p.Val37Ile variants utilizing professional variant interpretation guidelines and professional judgment. We found that p.Met34Thr and p.Val37Ile are significantly overrepresented in hearing loss patients, compared with population controls. Individuals homozygous or compound heterozygous for p.Met34Thr or p.Val37Ile typically manifest mild to moderate hearing loss. Several other types of evidence also support pathogenic roles for these two variants. Conclusion: Resolving controversies in variant classification requires coordinated effort among a panel of international multi-institutional experts to share data, standardize classification guidelines, review evidence, and reach a consensus. We concluded that p.Met34Thr and p.Val37Ile variants in GJB2 are pathogenic for autosomal recessive nonsyndromic hearing loss with variable expressivity and incomplete penetrance

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV

The performance of muon reconstruction, identification, and triggering in CMS has been studied using 40 inverse picobarns of data collected in pp collisions at sqrt(s) = 7 TeV at the LHC in 2010. A few benchmark sets of selection criteria covering a wide range of physics analysis needs have been examined. For all considered selections, the efficiency to reconstruct and identify a muon with a transverse momentum pT larger than a few GeV is above 95% over the whole region of pseudorapidity covered by the CMS muon system, abs(eta) < 2.4, while the probability to misidentify a hadron as a muon is well below 1%. The efficiency to trigger on single muons with pT above a few GeV is higher than 90% over the full eta range, and typically substantially better. The overall momentum scale is measured to a precision of 0.2% with muons from Z decays. The transverse momentum resolution varies from 1% to 6% depending on pseudorapidity for muons with pT below 100 GeV and, using cosmic rays, it is shown to be better than 10% in the central region up to pT = 1 TeV. Observed distributions of all quantities are well reproduced by the Monte Carlo simulation.Comment: Replaced with published version. Added journal reference and DO

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

The azimuthal anisotropy of charged particles in PbPb collisions at nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pt) range up to approximately 60 GeV. The data cover both the low-pt region associated with hydrodynamic flow phenomena and the high-pt region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with pt, reaching a maximum around pt = 3 GeV, and then to gradually decrease to almost zero, with the decline persisting up to at least pt = 40 GeV over the full centrality range measured.Comment: Replaced with published version. Added journal reference and DO